Problem: Which of the following numbers is a factor of 183? ${3,10,11,12,14}$
Solution: By definition, a factor of a number will divide evenly into that number. We can start by dividing $183$ by each of our answer choices. $183 \div 3 = 61$ $183 \div 10 = 18\text{ R }3$ $183 \div 11 = 16\text{ R }7$ $183 \div 12 = 15\text{ R }3$ $183 \div 14 = 13\text{ R }1$ The only answer choice that divides into $183$ with no remainder is $3$ $ 61$ $3$ $183$ We can check our answer by looking at the prime factorization of both numbers. Notice that the prime factors of $3$ are contained within the prime factors of $183$ $183 = 3\times61 3 = 3$ Therefore the only factor of $183$ out of our choices is $3$. We can say that $183$ is divisible by $3$.